Pilot/Controller Glossary 

3/21/24 

a. 

An airport clearance limit at locations with a standard/special instrument approach procedure. The CFRs 

require that if an instrument letdown to an airport is necessary, the pilot shall make the letdown in accordance 

with a standard/special instrument approach procedure for that airport, or 

b. 

An airport clearance limit at locations that are within/below/outside controlled airspace and without a 

standard/special instrument approach procedure. Such a clearance is NOT AUTHORIZATION for the pilot to 

descend under IFR conditions below the applicable minimum IFR altitude nor does it imply that ATC is 

exercising control over aircraft in Class G airspace; however, it provides a means for the aircraft to proceed to 

destination airport, descend, and land in accordance with applicable CFRs governing VFR flight operations. 

Also, this provides search and rescue protection until such time as the IFR flight plan is closed. 

(See INSTRUMENT APPROACH PROCEDURE.) 

CRUISE CLIMB

−

 A climb technique employed by aircraft, usually at a constant power setting, resulting in an 

increase of altitude as the aircraft weight decreases. 

CRUISING ALTITUDE

−

 An altitude or flight level maintained during en route level flight. This is a constant 

altitude and should not be confused with a cruise clearance. 

(See ALTITUDE.) 
(See ICAO term CRUISING LEVEL.) 

CRUISING LEVEL

−

 

(See CRUISING ALTITUDE.) 

CRUISING LEVEL [ICAO]

−

 A level maintained during a significant portion of a flight. 

CSP

−

 

(See CONSTRAINT SATISFACTION POINT) 

CT MESSAGE

−

 

An EDCT time generated by the ATCSCC to regulate traffic at arrival airports. Normally, a 

CT message is automatically transferred from the traffic management system computer to the NAS en route 

computer and appears as an EDCT. In the event of a communication failure between the traffic management 

system computer and the NAS, the CT message can be manually entered by the TMC at the en route facility. 

CTA

−

 

(See CONTROLLED TIME OF ARRIVAL.) 
(See ICAO term CONTROL AREA.) 

CTAF

−

 

(See COMMON TRAFFIC ADVISORY FREQUENCY.) 

CTOP

−

 

(See COLLABORATIVE TRAJECTORY OPTIONS PROGRAM) 

CTRD

−

 

(See CERTIFIED TOWER RADAR DISPLAY.) 

CURRENT FLIGHT PLAN [ICAO]

−

 The flight plan, including changes, if any, brought about by subsequent 

clearances. 

CVFP APPROACH

−

 

(See CHARTED VISUAL FLIGHT PROCEDURE APPROACH.) 

CWA

−

 

(See CENTER WEATHER ADVISORY and WEATHER ADVISORY.) 

CWT

−

 

(See 

CONSOLIDATED WAKE TURBULENCE.

) 

PCG C

−

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